1. Go to eZ Studio,
2. Click on +Create button,
3. Choose Landing page,
4. Fill all required data in the landing page configuration form,
5. Submit it,
6. Add a new block - content list block,
7. Click on the added block,
8. From the block top menu click on the Settings button,
9. The configuration form shows errors from the beginning and this is unexpected situation.

The field validation should be performed when trying to submit invalid data.